This article describes how to troubleshooting the issue.

 Issue: Failed to deploy OVF package. ThrowableProxy.cause A general system error occurred: Provider method implementation threw unexpected exception: com.vmware.vapi.std.errors.ServiceUnavailable: ServiceUnavailable (com.vmware.vapi.std.errors.service_unavailable) => { messages = [LocalizableMessage (com.vmware.vapi.std.localizable_message) => { id = com.vmware.vapi.endpoint.cis.ServiceUnavailable, defaultMessage = Service unavailable., args = [], params = , localized = }], data = , errorType = SERVICE_UNAVAILABLE }

When I deploying the VM (OVF package) it was deploy and getting this error.

Cause: Due to Network latency issue because vCenter and Esxi hosts are different location but added these esxi hosts into vCenter for managing.

Workaround solution: 

> OVF package placed into jump server(vm) where reside on same location of esxi hosts.

> Login the esxi host on we browsers on respective jump server.

> Esxi host also logged in same jump server.

> Now you can deploy the VM (OVF package).

> VM was deployed very fast without issue.